Site Size From Artifact Scatter Calculator
Observed artifact scatter convex hull area, not occupied settlement boundary or sample recovery completeness; local planar coordinates only. Caller independently establishes sample/context/calibration applicability; not definitive chronology, provenance, taxonomy, disease or human identity.
Description
An artifact scatter's convex hull encloses its measured outer points.
An artifact scatter's convex hull encloses its measured outer points.1
That geometric area can differ from occupation extent, site boundaries and surveyed coverage. Use Site Size From Artifact Scatter Calculator to evaluate the supplied inputs under the model explained below.
When to use Site Size From Artifact Scatter Calculator
Use Site Size From Artifact Scatter Calculator to evaluate the supplied inputs under the model explained below. Establish the units, measurement scope and model assumptions before entering values.
How to use Site Size From Artifact Scatter Calculator and understand its results
- Establish the units, measurement scope and model assumptions before entering values.
- Enter Observed artifact planar coordinates meters using the field table and validation rules below, then run the tool.
- Read Observed scatter convex hull area m2, Hull vertex coordinates meters; interpret the units, signs, ordering and unknown-value placeholders described below.
- Correct reported input errors and rerun. Apply successful results according to their specific meanings and check the assumptions before using them in a decision.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| observedArtifactPlanarCoordinatesMeters | Observed artifact planar coordinates meters | array of array | Required; constraints below |
Enter at least three finite local planar [x,y] coordinates in m. Sort x then y, build lower and upper monotone hull chains while discarding collinear interior points, and reject a degenerate hull with fewer than three vertices. Return hull vertices and absolute shoelace area in m². Repeated points can be accepted when a nondegenerate hull remains. No site-boundary inference, holes, geodesy or survey-completeness correction occurs.
scatterAreaM2=abs(Σ(x[i]y[i+1]−y[i]x[i+1]))/2 on the convex hull Use the field order, units and branch conditions described above.
| Output field | Meaning | Value type |
|---|---|---|
| observedScatterConvexHullAreaM2 | Observed scatter convex hull area m2 | number |
| hullVertexCoordinatesMeters | Hull vertex coordinates meters | array of arrays |
{
"input": {
"observedArtifactPlanarCoordinatesMeters": [
[
0,
0
],
[
2,
0
],
[
2,
2
],
[
0,
2
],
[
1,
1
]
]
},
"output": {
"observedScatterConvexHullAreaM2": 4,
"hullVertexCoordinatesMeters": [
[
0,
0
],
[
2,
0
],
[
2,
2
],
[
0,
2
]
]
}
}Limitations and assumptions
That geometric area can differ from occupation extent, site boundaries and surveyed coverage. Apply the exact scope and assumptions explained above.
All listed fields require explicit values. Unexpected fields, incorrect types, nonfinite numbers and sparse arrays fail validation. Domain-specific bounds, alignments and supported tokens are explained above; extremely large inputs or outputs can also be rejected. Input errors differ from successful false results, empty match lists and unknown-evidence placeholders.
Alternative or Complementary methods
Use Site Grid Coordinate Converter for a related task: A local site grid can be scaled, rotated and translated into a shared planar frame.
Use Site Catchment Radius Walk-Time Calculator for a related task: A catchment radius can be estimated from a travel budget and effective walking speed.
References
Similar or alternative tools
- Site Grid Coordinate Converter
A local site grid can be scaled, rotated and translated into a shared planar frame.
- Site Catchment Radius Walk-Time Calculator
A catchment radius can be estimated from a travel budget and effective walking speed.